Add Pokemon detail card with tabbed encounter/evolution views

Pokemon edit modal now shows three tabs (Details, Evolutions, Encounters)
instead of a single long form. Evolution chain entries are clickable to
open the EvolutionFormModal for direct editing. Encounter locations link
to admin route detail pages. Create mode shows only the form (no tabs).

Backend adds GET /pokemon/{id}/encounter-locations (grouped by game) and
GET /pokemon/{id}/evolution-chain (BFS family discovery). Extracts
formatEvolutionMethod to shared utility.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/src/app/schemas/pokemon.py

@@ -50,6 +50,21 @@ class RouteEncounterDetailResponse(RouteEncounterResponse):
     pokemon: PokemonResponse
 
 
+class PokemonEncounterLocationItem(CamelModel):
+    route_id: int
+    route_name: str
+    encounter_method: str
+    encounter_rate: int
+    min_level: int
+    max_level: int
+
+
+class PokemonEncounterLocationResponse(CamelModel):
+    game_id: int
+    game_name: str
+    encounters: list[PokemonEncounterLocationItem]
+
+
 # --- Admin schemas ---